Establishing how many people in the world are living with deafblindness is challenging because of limited recognition and understanding, along with a lack of screening and identification.
The challenges of finding reliable data
In many countries, deafblindness is not officially recognised as a distinct disability. This means that people with deafblindness are not clearly identified in data on disability collected by governments and other entities.
Stigma, discrimination and misunderstanding can also lead to people with deafblindness being hidden away. If they do not access formal services and are not known to their community, they may remain uncounted.
Even where data on deafblindness exists, it may not be reliable. This might be because of the type of questions that are asked, the definitions that are used, or the way that data has been collected and analysed.
Progress through research
In 2018, the World Federation of the Deafblind undertook the largest population-based analysis on deafblindness ever conducted as part of the first Global Report on the situation and rights of people with deafblindness. Using data from population-based surveys from countries across a range of regions and income groups, they were able to establish a stronger basis on which to estimate prevalence at a global level.
The WFDB’s research also distinguished between severe and mild forms of deafblindness. This was possible because some data used questions that highlighted the level of difficulty experienced by individuals in carrying out certain activities.
It is estimated that 0.2% of the world’s population is living with a severe form of deafblindness. A further 2% of people around the world are living with milder forms of deafblindness.*
How Sense International uses deafblindness data
In many places where we work, very little research has been carried out to understand the prevalence of deafblindness. Official estimates may exist, but our experience often tells another story.
Unless we have good reason to use different data, we apply the WFDB’s prevalence estimates to the latest population figures for a specific country to suggest how many people with deafblindness we believe to be living there. This approach means that our data may differ from statistics quoted by other entities.
Sometimes, our experience of working in communities gives us a strong basis for calculating prevalence estimates differently. We might also have access to other reliable data sources that provide a different picture in certain countries. In these cases, we may decide not to apply the WFDB’s estimates.
Whenever we give information about the prevalence of deafblindness, we will always provide a reference so that we are clear about where our estimates have come from.
Read more about the findings of the Global Report and download a copy here.
* World Federation of the Deafblind (WFDB), 2018 At risk of exclusion from CRPD and SDGs implementation: Inequality and persons with deafblindness.